Adaboost算法的并行化及其在目標分類中的應(yīng)用
本文關(guān)鍵詞: GPGPU MIC 目標分類 自適應(yīng)增強學習 車輛識別 出處:《華南理工大學》2015年碩士論文 論文類型:學位論文
【摘要】:目標分類處于智能視頻監(jiān)控分析系統(tǒng)中的關(guān)鍵環(huán)節(jié),因為當我們需要對視頻序列中的運動目標進行監(jiān)測時,要先檢測、再分類,最后才是運動軌跡分析和理解。其中,Adaboost(Adaptive Boosting,自適應(yīng)增強學習)分類算法應(yīng)用最為廣泛,其核心思想是針對同一個訓練集訓練不同的弱分類器,然后把這些弱分類器集合起來,構(gòu)成一個更強的最終分類器。但是要想獲得性能較好的Adaboost分類器,往往需要花費大量的時間在樣本訓練上。而且訓練算法需要占用較大的內(nèi)存空間,普通家用電腦由于自身計算能力方面能力的限制,Adaboost算法在普通電腦上難以開展。為了降低傳統(tǒng)Adaboost算法訓練時間,本文結(jié)合當下主流的多核協(xié)處理器——MIC和GPGPU,針對Adaboost特點開展了相關(guān)的并行優(yōu)化工作:1、對傳統(tǒng)Adaboost算法進行熱點分析,發(fā)現(xiàn)Adaboost算法在訓練弱分類器時,90%以上的耗時集中在特征值計算及排序上面;2、結(jié)合協(xié)處理器不同的硬件架構(gòu)及編程風格,在GPGPU平臺上采用并行雙調(diào)排序方式優(yōu)化排序,改變了原有數(shù)據(jù)的存儲方式,減少隨機訪存的時間,提高了樣本訓練速度。此外,本文還針對MIC平臺開展了相應(yīng)的并行優(yōu)化實驗,對熱度相對集中的函數(shù)使用MPI/OpenMP等并行編程工具進行并行化,且細分為粗粒度并行以及細粒度并行兩種優(yōu)化策略。在樣本數(shù)為25600,樣本大小為18*18,MIC與GPGPU分別獲得3.8和7.2加速比。實驗表明,GPGPU在處理圖像數(shù)據(jù)方面更為出色。為了提高算法分類準確率,在樣本選取方面,本文提出了新型的樣本采集方式,在對車輛進行識別時,極大提高了原算法的檢測精度。此外,針對目標分類檢測過程中速度較慢的問題,提出了并行優(yōu)化方案。
[Abstract]:Target classification is a key step in the intelligent video surveillance and analysis system, because when we need to monitor the moving targets in video sequences, we must first detect and then classify. Finally, the analysis and understanding of motion trajectory. Among them, Adaboostan Adaptive boost (Adaptive Enhancement Learning) classification algorithm is the most widely used. Its core idea is to train different weak classifiers for the same training set, and then set these weak classifiers together. To form a stronger final classifier, but to obtain a better performance Adaboost classifier. It often takes a lot of time to train samples, and the training algorithm needs to occupy a large amount of memory space. The common home computer is limited by its own computing ability. In order to reduce the training time of traditional Adaboost algorithm, this paper combines the current mainstream multi-core coprocessor, MIC and GPGPU. According to the characteristics of Adaboost, the parallel optimization work: 1 is carried out. The focus of traditional Adaboost algorithm is analyzed, and it is found that Adaboost algorithm is training weak classifier. The time consuming over 90% is concentrated on the calculation and ranking of eigenvalues; 2. Combined with the different hardware architecture and programming style of the coprocessor, the parallel double-tone sorting method is adopted to optimize the sorting on the GPGPU platform, which changes the storage mode of the original data and reduces the time of random memory access. The training speed of the sample is improved. In addition, the parallel optimization experiments are carried out for the MIC platform. The functions with relatively concentrated heat are parallelized by parallel programming tools such as MPI/OpenMP and subdivided into coarse-grained parallelism and fine-grained parallelism. The number of samples is 25600. The sample size is 18 ~ (18) mics and GPGPU is 3. 8 and 7. 2 speedup ratio, respectively. The experiment shows that. In order to improve the classification accuracy of the algorithm, in the aspect of sample selection, this paper proposes a new way to collect samples, which is used to identify vehicles. The detection accuracy of the original algorithm is greatly improved. In addition, a parallel optimization scheme is proposed to solve the problem of slow speed in the process of target classification detection.
【學位授予單位】:華南理工大學
【學位級別】:碩士
【學位授予年份】:2015
【分類號】:TN948.6;TP301.6
【參考文獻】
相關(guān)期刊論文 前9條
1 孫偉平;向杰;陳加忠;余勝生;;基于GPU的粒子濾波并行算法[J];華中科技大學學報(自然科學版);2011年05期
2 程峰;李德華;;基于CUDA的Adaboost算法并行實現(xiàn)[J];計算機工程與科學;2011年02期
3 郭靜;陳慶奎;;基于CUDA的快速圖像壓縮[J];計算機工程與設(shè)計;2010年14期
4 左登宇;董蘭芳;宋波;;Adaboost人臉檢測方法及其并行實現(xiàn)[J];計算機仿真;2010年06期
5 趙雪竹;王秀;朱學峰;;基于Adaboost算法的人眼檢測中樣本選擇研究[J];計算機技術(shù)與發(fā)展;2010年02期
6 左顥睿;張啟衡;徐勇;趙汝進;;基于GPU的快速Sobel邊緣檢測算法[J];光電工程;2009年01期
7 明安龍;馬華東;;多攝像機之間基于區(qū)域SIFT描述子的目標匹配[J];計算機學報;2008年04期
8 王海川,張立明;一種新的Adaboost快速訓練算法[J];復旦學報(自然科學版);2004年01期
9 王亮,胡衛(wèi)明,譚鐵牛;人運動的視覺分析綜述[J];計算機學報;2002年03期
相關(guān)碩士學位論文 前4條
1 李紅艷;交通監(jiān)控系統(tǒng)中的運動目標檢測與分類[D];太原科技大學;2012年
2 朱建清;智能視頻監(jiān)控系統(tǒng)中的人臉檢測和人臉跟蹤技術(shù)的研究[D];華僑大學;2012年
3 陳翰波;基于部分集分類器和并行計算的人臉檢測訓練[D];中南大學;2011年
4 劉麗麗;基于形狀特征的運動目標分類方法研究[D];湖南大學;2006年
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